The Harvard Observatory.

The astronomical observatory submitted its annual report to the visiting committee on Jan. 10. An urgent request is made for a fire proof building for the records of observations, valuable instruments and especially the collection of about 27.000 glass photographic plates representing the stars and spectra of both the northern and southern heavens, the results of observations in Peru. California and Cambridge. These are now stored in a frame building, the only one available where they could be destroyed by fire in a few minutes. Besides the plates there is a large collection of manuscripts which if once destroyed could never be replaced. Since the last annual report, in which the death of Mr. Bowditch, one of the greatest benefactors to the observatory, was taken note of, it has been learned that he left an additional bequest of $2.500.00.

The large equatorial telescope has been used during the year in the photometric observation of twenty-one eclipses of Jupiter's satellites, making in all 151 since 1877; in obtaining positions of several comets; in the systematic observations of variable stars; and in photometric observation of zones of stars. The principal observer was Mr. O. C. Wendell. The reduction of observations made in former years with the meridian circle by Professor W. A. Rogers continues under his supervision, and the catalogue of the stars observed between 50 degrees and 55 degrees north of the equator is mostly in print. A similar catalogue of stars between 10 degrees and 14 degrees south of the equator is at present in course of observation by Professor Searle and Mr. Dunne. Occasional observations have been made with the six-inch equatorial mounted in the west dome.

The photographing of the heavens has continued at Cambridge and at Pern by the Draper memorial fund, where at Chosica Mr. B dev has taken 1,309 photographs including almost the entire southern heaven from 20 degrees south of the equator to the south pole.

Mrs. D Aper has given a photographic telescope 8 inches per hour for use in Cambridge, where 2.157 photographs have been taken making a chart of the sky from the north pole to 20 degrees south of the equator. Spectrit of stars as faint as the tenth magnitude have been obtained and umerous is important results obtained. The most interesting result has been the discovery by Miss Maury of a second star, Beta Aurigael, which is shown by the doubling of the lines in its spectrum at regular intervals to be a close binary, revolving once in about four days. The study of the star of this class previously known. Zeta Ursae M joris, has been continued.

Work under the boyden fund has been continued in Pern California and Cambridge in the last of which places Professor Pickering took personal charge of the work, making observations on Mars and experimenting in astronomical photography. Researches were made on the meteorology of the earth and on the nebulous region in Orion.

In August the instruments on Wilson's Peak in California were sent to Cambridge for shipment to Areguipa in Pern, the location chosen for further observations. Great service was rendered the expedition by Hon. John Hicks, American minister to Pern, and Senor L. L. De Rumma of Areguipa, under whose direction valuable meteorological observations were made.

The disks of glass for the projected Bruce photographic telescope have not yet been received from France, but the disk for the prism has been received and seems to be unusually free from defects. The important gift by Miss Bruce of six thousand dollars, to be distributed among astronomers of all nations should here be mentioned. It affords an example of using money so as to secure the greatest scientific return, which, it is hoped, will find many imitators.

The library of the observatory has been increased by 311 volumes and 856 pamphlets, the total numbers being now 6767 volumes and 6891 pamphlets.

The time service has been continued and a new line of telegraph recently constructed for the purpose has improved the transmission of the signals. The Boston time bill was dropped on 286 week days, automatically, by telegraph at noon.

The distribution of telegraphic news of astronomical discoveries has been continued under the management of Mr. Ritchie and has required in all 278 telegrams and 14 cable messages.

Three volumes of "Annals of the Observatory" have been completed and published during the year; the publication of eight others is in progress, several of them being very nearly complete at the close of the year and thirty minor publications were made in astronomical periodicals or separately.